A reversible fan is known in which individual fan blades are rotatable manually to place the fan blades into either reverse or normal thrust positions. Such a fan is available from Huber Reversible Fan Inc. of Pennsylvania, United States, and also described in U.S. Pat. No. 4,606,702. Such fans are used on a wide variety of industrial equipment and vehicles that have engines.
The inventors have identified a need for a reversible fan in which rotation of one fan blade rotates all the fan blades.